Thursday, September 12, 2013

Mite Sampling: 09-10-2013

I hate to even talk about this because just the thought of mites sucking the blood (hemolymph) out of my bees and perhaps transferring diseases to them pisses me off!! But the Varroa Mite, is now an integral part of any beekeeper's management and there is no escaping their impact. So, what to do? I long ago decided I want no antibiotics or chemicals in my hives, so those kind of treatments are out. This leaves me with various IPM (Integrated Pest Management) techniques to use. Before you use any of those techniques, you need to determine what kind of mite load your hive is currently dealing with. Of course, there are numerous ways of doing mite sampling and there is a great article here scientificbeekeeping.com about the different techniques and why you would or wouldn't use them. I decided to start my sampling by doing the sticky board drop test. It isn't perfect, but it is quick and easy and a good place to start!

Mite Drop Test:
All you do to perform this test is put a board with a sticky substance on it underneath a hive that has a screened bottom. You leave this on for a few days and then take it off and count the mites.

I put some vegetable oil on the board (next time I'll use vaseline) and put the board under the hive for 48 hours and this is what I found:

What you end up seeing is a plastic sheet covered by bee debris. The debris consists of pollen, dripped honey, dust, dirt, a bee leg or two and some mites. This is one of the reason you don't leave the board on for too long....you can't spot the mites because of all the debris.

Here is a close up of the debris:

See any mites? The big chunks of pollen are pretty easy to spot but telling the difference between a piece of dirt and a mite is a bit more difficult. Here are the mites:

If you look very closely you can see the legs sticking out from their body. Once you get a feel for the size, shape and color, they become easier to spot.

Counting the mites, I ended up with a total of 21. Divide that by the number of days and you get just over 10 dropped per day. There doesn't seem to be any rule set in stone that says "if you have this many then you need to do this", so right now this will be a baseline number that I use as a comparison. I believe this is a relatively "low" number for this time of year, but I will plan on doing more tests in the future. It is easy enough to clean off the board and put it back on the hive for a few days.

I would like to try the powdered sugar jar sampling method in the future. That sounds interesting, you don't end up killing the bees, and you end up with a bunch of powdered sugar covered ghost bees walking around your hive for a while!!

Until next time, thanks for reading and I hope my mite numbers go down!